Method and system for monitoring power transformers

摘要

The present invention relates to a method and a system of monitoring power transformers, intended to detect incipient failures in a transformer. For this purpose, only sensors external to the transformer are used, or sensors that can be installed without needing to untank the transformer. The detection of the incipient failures is carried out based on mathematical models of behaviour, so that for the identification of the fault conditions a set of measured variables is compared, with some adaptive threshold values for each variable calculated from the operating conditions of the transformer. The mathematical models comprise a thermal model, a vibration model and a model of moisture in the oil.